//------------------------------------------------------------------------
// LowerStoreLoc: Lower a store of a lclVar
//
// Arguments:
// storeLoc - the local store (GT_STORE_LCL_FLD or GT_STORE_LCL_VAR)
//
// Notes:
// This involves:
// - Widening operations of unsigneds.
//
void Lowering::LowerStoreLoc(GenTreeLclVarCommon* storeLoc)
{
// Try to widen the ops if they are going into a local var.
GenTree* op1 = storeLoc->gtGetOp1();
if ((storeLoc->gtOper == GT_STORE_LCL_VAR) && (op1->gtOper == GT_CNS_INT))
{
GenTreeIntCon* con = op1->AsIntCon();
ssize_t ival = con->gtIconVal;
unsigned varNum = storeLoc->gtLclNum;
LclVarDsc* varDsc = comp->lvaTable + varNum;
if (varDsc->lvIsSIMDType())
{
noway_assert(storeLoc->gtType != TYP_STRUCT);
}
unsigned size = genTypeSize(storeLoc);
// If we are storing a constant into a local variable
// we extend the size of the store here
if ((size < 4) && !varTypeIsStruct(varDsc))
{
if (!varTypeIsUnsigned(varDsc))
{
if (genTypeSize(storeLoc) == 1)
{
if ((ival & 0x7f) != ival)
{
ival = ival | 0xffffff00;
}
}
else
{
assert(genTypeSize(storeLoc) == 2);
if ((ival & 0x7fff) != ival)
{
ival = ival | 0xffff0000;
}
}
}
// A local stack slot is at least 4 bytes in size, regardless of
// what the local var is typed as, so auto-promote it here
// unless it is a field of a promoted struct
// TODO-CQ: if the field is promoted shouldn't we also be able to do this?
if (!varDsc->lvIsStructField)
{
storeLoc->gtType = TYP_INT;
con->SetIconValue(ival);
}
}
}
if (storeLoc->OperIs(GT_STORE_LCL_FLD))
{
// We should only encounter this for lclVars that are lvDoNotEnregister.
verifyLclFldDoNotEnregister(storeLoc->gtLclNum);
}
ContainCheckStoreLoc(storeLoc);
}
//------------------------------------------------------------------------
// TreeNodeInfoInitStoreLoc: Set register requirements for a store of a lclVar
//
// Arguments:
// storeLoc - the local store (GT_STORE_LCL_FLD or GT_STORE_LCL_VAR)
//
// Notes:
// This involves:
// - Setting the appropriate candidates for a store of a multi-reg call return value.
// - Handling of contained immediates.
//
void Lowering::TreeNodeInfoInitStoreLoc(GenTreeLclVarCommon* storeLoc)
{
ContainCheckStoreLoc(storeLoc);
TreeNodeInfo* info = &(storeLoc->gtLsraInfo);
GenTree* op1 = storeLoc->gtGetOp1();
info->dstCount = 0;
#ifdef _TARGET_ARM_
if (varTypeIsLong(op1))
{
info->srcCount = 2;
assert(!op1->OperIs(GT_LONG) || op1->isContained());
}
else
#endif // _TARGET_ARM_
if (op1->isContained())
{
info->srcCount = 0;
}
else if (op1->IsMultiRegCall())
{
// This is the case of var = call where call is returning
// a value in multiple return registers.
// Must be a store lclvar.
assert(storeLoc->OperGet() == GT_STORE_LCL_VAR);
// srcCount = number of registers in which the value is returned by call
GenTreeCall* call = op1->AsCall();
ReturnTypeDesc* retTypeDesc = call->GetReturnTypeDesc();
info->srcCount = retTypeDesc->GetReturnRegCount();
// Call node srcCandidates = Bitwise-OR(allregs(GetReturnRegType(i))) for all i=0..RetRegCount-1
regMaskTP srcCandidates = m_lsra->allMultiRegCallNodeRegs(call);
op1->gtLsraInfo.setSrcCandidates(m_lsra, srcCandidates);
}
else
{
info->srcCount = 1;
}
}
